A sensorless control method and device for a permanent magnet synchronous motor

Abstract

The invention provides a sensorless control method and device for a permanent magnet synchronous motor, which does not require a motor rotor position sensor and a back electromotive force detection circuit in the control process, thereby reducing the hardware complexity; The acceleration and deceleration control of the motor rotor can still make the motor run normally without the motor rotor position sensor; the motor angle is calculated by detecting the change of the flux linkage sector, and the motor speed is calculated by differential and smooth filtering. In the case of the sensor, the motor speed information can still be obtained. The method of the invention calculates the flux linkage angle by measuring the two-phase winding current in the three-phase motor, and judges the flux linkage sector according to the flux linkage angle; The winding generates a rotating magnetic field, controls the motor rotation, and calculates the motor speed according to the change of the flux linkage sector, and outputs it after smoothing and filtering.

Description

technical field [0001] The invention belongs to the field of aerospace, and relates to a sensorless control method and device of a permanent magnet synchronous motor. Background technique [0002] At present, servo motors represented by permanent magnet synchronous motors are equipped with rotor position sensors on the motor shaft, which are not only used to measure the motor speed but also provide input signals for motor drive control. In the aerospace field, due to the requirements of spacecraft weight reduction design, sensors often have no backup. Therefore, when the sensor fails, the motor will not be able to operate in the normal mode, resulting in the failure of the movement function of the mechanism and affecting the completion of the spacecraft mission. [0003] Patent Publication No. CN104167961A "A Motor Sensorless Drive Control System" proposes a drive circuit and control method for a high-speed motor (rotational speed 10000rpm~120000rpm), however, the drive circ...

AI Technical Summary

Problems solved by technology

In the field of aerospace, due to the requirement of spacecraft weight reduction design, the sensor often has no backup. Therefore, when the sensor fails, the motor will not be able to operate in the normal mode, resulting in the failure of the mechanism’s motion function and affecting the completion of the mission of the spacecraft.

[0003] The patent "A Motor Sensorless Drive Control System" with publication number CN104167961A proposes a drive circuit and control method for high-speed motors (rotating speed 10,000rpm-120,000rpm). However, the drive circuit proposed in this patent must have a dedicated However, the controller of the spacecraft motor is limited by the size and power consumption, so it is difficult to increase the circuit. At the same time, the speed of the spacecraft motor is generally only between 300 and 1200rpm, so this patent cannot solve the problem of the spacecraft motor. Technical Difficulties of Sensorless Control

Images